Wall angles - Is there a quicker way of achieving this result?
There are a few ways to do this. My personal choice is to use a curve representing the wall shape as the bevel object for another curve representing the floor plan.


Create a mesh object with the outline of the wall shape you want to use, such as this
Convert it to a curve (ALT-C -> Curve from Mesh)
Create a floor plan and convert it to a curve, such as this
Use the wall shape as the bevel object for the floor plan


You can create the curves directly if you prefer and you can convert the beveled curve to a mesh (ALT-C -> curve to mesh) so that you can modify it.